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Introduction: Partial or complete obstruction of the urinary tract is a common and challenging urological condition that may occur in patients of any age. Serum creatinine is the most commonly used method to evaluate global renal function, although it has low sensitivity for early changes in the glomerular filtration rate or unilateral renal pathology. Hence, finding another measurable parameter that reflects the adaptation of the renal physiology to these circumstances is important. Several recent studies have assessed the use of new biomarkers of acute kidney injury (AKI), but the information among patients with stone disease and those with obstructive uropathy is limited., Material and Methods: A prospective cohort study was conducted to determine the urinary levels of kidney injury molecule-1 (KIM-1), Total and Monomeric neutrophil gelatinase-associated lipocalin (NGAL) in patients with hydronephrosis secondary to renal stone disease, congenital ureteropelvic junction obstruction or ureteral stricture. Comparison between patients with hydronephrosis and no hydronephrosis was carried out along with correlation analysis to detect factors associated with biomarker expression., Results: Urinary levels of KIM-1 significantly decreased after hydronephrosis treatment in patients with unilateral obstruction (1.19 ng/mL vs 0.76 ng/mL creatinine, p = 0.002), additionally KIM-1 was significantly higher in patients with hydronephrosis compared to stone disease patients without radiological evidence of obstruction (1.19 vs 0.64, p = 0.006). Total and Monomeric NGAL showed a moderate correlation with the presence of leukocyturia. We found that a KIM-1 value of 0.735 ng/mg creatinine had a sensitivity of 75% and specificity of 67% to predict the presence of hydronephrosis in preoperative studies (95% CI 0.58-0.87, p = 0.006)., Conclusion: Our results show that KIM-1 is a promising biomarker of subclinical AKI associated with hydronephrosis in urological patients. NGAL values were influenced by the presence of leukocyturia, limiting its usefulness in this population.

Purpose: This study evaluates the safety and efficacy of intravesical ropivacaine as part of a mulitimodal approach to the provision of analgesia after robot-assisted radical prostatectomy (RARP)., Patients and Methods: In this double-blind, placebo-controlled trial, 40 patients who were scheduled to undergo RARP for treatment of localized prostate cancer by a single surgeon (SP) were randomized 1:1 to receive either alkalinized intravesical ropivacaine or placebo (0.9% sodium chloride) at the completion of the vesicourethral anastomosis. A standardized general anesthetic was administered in each case. The primary outcome was a reduction in postoperative pain as assessed by a visual analogue scale (VAS). The need for alternate analgesic agents was recorded. Adverse events related to the administration of intravesical ropivacaine were documented prospectively., Results: No serious adverse events related to the administration of intravesical ropivacaine were identified. In the ropivacaine group, there was a significant reduction in the cumulative needed dose of ketoralac relative to placebo at 6 hours postoperatively. There was no statistically significant difference between the groups with regard to pain scores or narcotic use at any time point., Conclusions: Intravesical administration of ropivacaine may be used safely in the context of RARP and is associated with a significant, albeit modest reduction in the need for supplementary analgesic agents, but did not result in a decrease in postoperative pain scores.

Purpose: To evaluate a materials model for laparoscopic ultrasound identification and partial nephrectomy of kidney tumors., Methods: Five urology fellows performed laparoscopic ultrasonography (LUS) examination of the tumor model, and the time for identification was recorded. After identifying the tumor, they performed a laparoscopic partial nephrectomy using the target tumor with measurement of operative parameters. They completed a questionnaire and rated the quality of the renal tumor model on a 5-point Likert scale., Results: The participants were able to identify 49 tumors by LUS (98%). The mean time to identify the renal tumors by LUS was 1.12 minutes ± 0.93 standard deviation (SD). A partial nephrectomy was successfully completed on 49 tumor models (98%). The mean resection time was 7.69 minutes ± 3.8 SD. All of the participants considered that this model was helpful in the practice of LPN. The fellows would recommend this model as a teaching tool for residents/fellows to perform tumor imaging by LUS and for practicing LPN in a simulated environment., Conclusion: We have developed a unique model that simulates small kidney tumors that can be used for training surgeons in the clinical skills of laparoscopic partial nephrectomy.

Background and Purpose: The da Vinci(®) surgical system requires the use of electrosurgical instruments. The re-use of such instruments creates the potential for stray electrical currents from capacitive coupling and/or insulation failure. We used objective measures to report the prevalence and magnitude of such stray currents., Materials and Methods: Thirty-seven robotic instruments were tested using an electrosurgical unit (ESU) at pure coagulation and cut waveforms at four different settings. Conductive gel-coated instruments were tested at 40W, 80W, and maximum ESU output (coagulation 120W, cut 300W). The magnitude of stray currents was measured by an electrosurgical analyzer., Results: At coagulation waveform in open air, 86% of instruments leaked a mean of 0.4W. In the presence of gel-coated instruments, stray currents were detected in all instruments with means (and standard deviation) of 3.4W (± 2), 4.1W (± 2.3), and 4.1W (± 2.3) at 40W, 80W, and 120W, respectively. At cut waveform in open air, none of the instruments leaked current, while gel-coated instruments leaked a mean of 2.2W (± 1.3), 2.2W (± 1.9) and 3.2W (± 1.9) at 40W, 80W, and 300W, respectively., Conclusions: All tested instruments in our study demonstrated energy leakage. Stray currents were higher during coagulation (high voltage) waveforms, and the magnitude was not always proportionate to the ESU settings. Stray currents have the potential to cause electrical burns. We support the programmed end of life of da Vinci instruments on the basis of safety. Consideration should be given to alternate energy sources or the adoption of active electrode monitoring technology to all monopolar instruments.

Purpose: To evaluate a materials model for laparoscopic guided cryotherapy or radiofrequency tissue ablation (RFA) of kidney tumors through expert surgeon assessment., Materials and Methods: During the inaugural American Urological Association 2010 Tissue Ablative course content, validity testing of a renal tumor model was undertaken. Five expert faculty in cryotherapy and RFA techniques for renal tumors performed laparoscopic ultrasonography (US) examination of the tumor model. They performed US guided placement and activation of the treatment probe into the tumor of the model. They completed a questionnaire and rated the quality of the renal tumor model on a 5 point Likert scale., Results: All of the subjects assigned a score of 5 of 5 on the Likert scale regarding the ability to identify the tumor with US, were able to deploy the ablative probe into the model under US guidance, and would recommend the use of this teaching model to residents or fellows. They thought that this tumor model was appropriate for teaching laparoscopic US imaging of a renal tumor during ablative treatment procedures, teaching and practicing laparoscopic US-guided cryotherapy, and teaching and practicing laparoscopic US-guided RFA., Conclusion: We have developed a unique model that simulates small kidney tumors that can be used for training surgeons in ablative techniques.

Background and Purpose: The incidence of incisional hernia after robot-assisted radical prostatectomy (RARP) has not been described previously. We report our prospective data in an attempt to identify factors that may predispose to this important complication., Patients and Methods: The information contained in our prospectively collected RARP database was used to assess the incidence and predisposing factors for incisional hernia post-RARP in a single surgeon series of 250 patients., Results: The incidence of incisional hernia in our series was 4.8% (12 of 250 patients). Statistical analysis demonstrated a higher rate of incisional hernias in patients for whom the supraumbilical incision for specimen retrieval was closed with a continuous, rather than interrupted suture. Incisional hernia is associated with a significantly longer length of hospital stay., Conclusion: Urologists should be aware that incisional hernia is an important postoperative complication after RARP. Closure of linea alba with a nonabsorbable suture using an interrupted technique may help to minimize the incidence of this morbid complication.

Background and Purpose: Robot-assisted pyeloplasty (RAP) has been established recently as an option in the management of ureteropelvic junction obstruction (UPJO). We present the first Canadian experience with RAP with respect to operative results and outcomes. We compare the surgical outcomes between experienced and trainee surgeons, with respect to operating room times and success rates., Patients and Methods: Eighty-eight patients underwent transperitoneal RAP for UPJO using the da Vinci robotic platform. Two surgeons performed Anderson-Hynes dismembered pyeloplasty in 85 cases and YV-plasty in 5 cases. Five patients had RAP for secondary UPJO after failure of other treatments. Diuretic renography was performed at 6 weeks, and 6, 12, 18, 24, and 36 months postpyeloplasty. The mean follow-up was 14.1 ± 8.5 months., Results: The mean operative time was 167.7 ± 43.2 minutes, and the mean anastomotic time was 41.9 ± 14.1 minutes. The mean operative duration significantly decreased with time (P < 0.05). Ten patients needed simultaneous nephroscopic stone management via the pyelotomy incision. The mean blood loss was 56.6 ± 55.4 mL, and the mean hospital stay was 2.5 ± 0.5 days. There were five major postoperative (stent migration, urinoma) and three minor complications that were associated with the RAP procedures. Postoperative renal scintigraphy demonstrated only four cases with persistent obstruction. Eighty-three (94.3%) patients experienced improvement of symptoms whereas 5 continued to be symptomatic. Two patients needed secondary procedures to relieve persisting obstruction. There were no statistical differences in outcomes between the experienced surgeons and trainees (P = 0.28)., Conclusions: In the first large case series of RAP from Canada, we demonstrate that RAP can be performed with relatively short operative times and is safe and effective, achieving similar long-term results with standard open repair. We show that robot-assisted surgery can be safely transitioned to surgical trainees. With its cost and availability, its role in the Canadian system needs further study.

Background and Purpose: Widespread introduction of robot-assisted laparoscopic radical prostatectomy (RALRP) has led to multiple surgeons going through the learning curve (LC). One of the recommendations for surgeons on the LC for RALRP is to choose patients with smaller glands. We evaluated our LCs to determine whether prostate size influenced intraoperative outcomes and positive surgical margin rates., Patients and Methods: Data were obtained from a prospective database for the first 154 cases of RALRP performed by a single surgeon. Patients were divided into three groups based on prostate volume (PV): <40 cc (group 1), 40 to 60 cc (group 2), or >60 cc (group 3). PV was estimated by preoperative transrectal ultrasonography (TRUS) and correlated with pathologic weight (PW). Perioperative and immediate postoperative outcomes were evaluated., Results: A statistically significant difference in total operative times between the groups (206 minutes vs 201 minutes vs 233 minutes for groups 1, 2, and 3, respectively) was noted. With regard to individual intraoperative steps, the bladder neck reconstruction and anastomosis time was longer in group 3. No other statistically significant differences were noted. The Pearson correlation coefficient between PV estimation by TRUS and PW was r = 0.785, and an additional analysis based on PW supports the results of our study., Conclusions: Prostate size influenced total operative times and the bladder neck reconstruction and anastomosis time. Our data support the use of preoperative TRUS to estimate PV and recommendations for surgeons starting on their LC to choose glands less than 60 cc.

Background and Purpose: Ureteral stents may cause significant morbidity, including pain, dysuria, hematuria, and infection. New biomaterials, coatings, and designs have been studied in an attempt to reduce stent-related symptoms, but to date, the ideal comfortable stent has not been developed. In order to facilitate development of a stent that will mold and change with patient movement, we examined stent and ureteral movement with changes in patient body position., Patients and Methods: Four women and two men with a median age of 60.5 +/- 7.7 years who underwent shockwave lithotripsy and insertion of a ureteral stent were enrolled. Static radiographs were performed with the patients in four positions: supine, standing, sitting, and bending forward. Differences in stent position were analyzed digitally relative to fixed bony reference points to determine ureteral movement., Results: The renal stent curl was most cephalad when the patient was supine and moved caudally an average of 2.5 +/- 1.5 cm when the patient stood up. The absolute vertical length of the stent was greatest when the patient was supine (31.1 +/- 1.2 cm) and shortened with standing (28.3 +/- 2.3 cm) and sitting (26.6 +/- 1.5 cm). The bladder curl moved an average of 2.3 +/- 1.2 cm vertically with patient movement., Conclusions: By measuring stent position, we were able to quantify the range of motion of the ureter during changes in body position. Stent movement appears to be a combination of bowing in the proximal ureter and moving within the bladder. Future stent designs may take this into account to decrease stent-related symptoms.

Background and Purpose: The gold standard treatment for upper-tract transitional-cell carcinoma is radical nephroureterectomy, but management of the distal ureter is not standardized. Two treatment options to detach the distal ureter are open cystotomy (OC) and excision of a bladder cuff or transurethral incision of the ureteral orifice (TUIUO). We compared the clinico-pathologic outcomes of these two techniques., Patients and Methods: Hospital records were reviewed on all 51 patients who had undergone open or laparoscopic nephroureterectomy at our institution between 1 January 1990 and 30 June 2005. Patient demographics, intraoperative parameters, and pathology data were collected. The mean follow-up was 23.2 months (range 4.5-75 months) and 22.1 months (range 1-50 months) for the OC and TUIUO groups, respectively. There were no significant differences in sex, age at operation, American Society Anesthesiologists risk score, previous transitional-cell tumors, pathologic tumor grade and stage, or metastatic disease status in the two groups., Results: Five patients had an unplanned incomplete ureterectomy. The bladder recurrence rates were similar in the OC group (22.2%; 6/27) and the TUIUO group (26.3%; 5/19). There were no pelvic recurrences in either group. Four of the five patients who had an incomplete ureterectomy had tumor recurrences, three in the form of metastatic disease., Conclusion: Management of the distal ureter by TUIUO in appropriate patients offers the same rate of bladder recurrence as OC. Incomplete ureterectomy results in a significantly higher rate of recurrence, often associated with the development of metastatic disease.

The gold standard treatment for supravesical urothelial carcinoma has been open radical nephroureterectomy based on the premise that this cancer is a field defect. However, nephroureterectomy is an extensive procedure that may not be tolerated by all patients. Percutaneous and ureteroscopic approaches have been utilized in an attempt to avoid the potential morbidity associated with traditional open surgery. This review provides an update on percutaneous management of upper-tract urothelial transitional-cell cancer based on a review of the pertinent literature.

Background and Purpose: Ureteral stents are a significant source of pain and discomfort for many urologic patients. A novel approach to addressing this problem is the intravesical instillation of a selected pharmacologic agent after stent insertion. The purpose of this study was to assess the safety and efficacy of intravesical instillation of various agents in reducing ureteral stent-associated discomfort in patients requiring a stent after extracorporeal shockwave lithotripsy (SWL)., Patients and Methods: In this double-blind prospective trial, 42 patients were randomized to receive intravesical instillation of one of three agents (oxybutynin, alkalinized lidocaine, or ketorolac) or a control solution (0.9% sodium chloride) immediately after stent insertion at time of SWL. The four groups of patients were demographically similar. Preoperative, intraoperative, and postoperative data were collected prospectively and analyzed statistically. The primary outcome measure was reduction in ureteral stent symptoms, and the secondary outcome measure was the safety of intravesical instillation of each agent through assessment of drug-related adverse events., Results: There were no intraoperative or postoperative complications, nor were there any serious side effects attributable to any of the intravesically instilled agents. There was a statistically significant decrease in stent-related discomfort at the 1-hour time point in the group of patients who received intravesical ketorolac compared with the control group., Conclusions: Intravesical instillation represents a novel approach to the problem of ureteral stent-related discomfort. From our results, ketorolac appears to be the most effective intravesical agent in reducing stent-related patient discomfort, and we have established that intravesical instillation of ketorolac is safe in humans.

Background and Purpose: Laparoscopic radical nephrectomy (LRN) is being increasingly offered for the management of renal-cell carcinoma (RCC). Specimen removal may be performed through a small or hand-port incision or by specimen morcellation. Limited studies exist addressing the accuracy of histopathologic diagnosis in morcellated renal tumors. Because of concerns about the lack of a diagnosis secondary to the morcellation process, we performed premorcellation needle biopsies to obtain nondisrupted tissue for pathologic analysis. Herein, we compare the histopathologic diagnosis achieved via needle biopsy prior to morcellation with that of the final specimen., Patients and Methods: Following successful laparoscopic resection, specimens were entrapped in a Lapsac. Needle biopsies were performed manually through the mouth of the Lapsac, and morcellation was then done in some patients using manual and mechanical methods. The histopathologic diagnoses in the needle biopsy specimens and the morcellated material were compared., Results: Laparoscopic radical nephrectomy with specimen morcellation was performed in 15 patients. Nine patients had premorcellation needle biopsies. Eight of these biopsies had sufficient tissue for diagnosis of RCC. This finding correlated with final diagnosis from the morcellated material. Perinephric fat invasion was identified in three morcellated specimens., Conclusions: Needle biopsy prior to specimen morcellation confirmed the histologic diagnosis of the morcellated specimen. This finding suggests that such histopathology material is adequate for diagnosis and may make premorcellation needle biopsy redundant.

We report a case of an unusual uroepithelial cyst arising from a renal calix in an African-American man with sickle cell trait. The lesion was incised and decompressed using a 7.5F flexible ureteroscope in conjunction with the holmium:YAG laser and a 200-microm quartz laser fiber. To our knowledge, endourologic management of this type of lesion has not been described in the literature.